Automated tape splicing system

ABSTRACT

A multi-roll automatic tape splicing device includes a platen which is rotatably mounted on a support frame via a shaft. Two or more tape mandrels are rotatably disposed on the platen at a substantially equal distance from the shaft, and substantially equally spaced from each other, each mandrel being capable of receiving a respective roll of tape. An index drive is operatively coupled to the platen, for selectively rotating the platen so as to successively move each mandrel into a predetermined operating position at which a web of tape can be drawn from a respective roll of tape disposed on the mandrel, and for moving a mandrel out of the operating position when the respective roll of tape is depleted. A first sensor is operatively mounted on the support frame and capable of detecting a depleted condition of a roll of tape mounted on a respective mandrel in the operating position. A second sensor is operatively mounted on the support frame and capable of detecting rotation of a mandrel in the operating position. A cutting unit is disposed on the frame and capable of severing a web of tape being drawn from a depleted roll of tape. A control unit is responsive to the first and second sensors such that when the first sensor detects a depleted condition of a roll of tape, the control unit controls the index drive to rotate the platen and thereby move the next successive mandrel into the operation position. A tab formed on the end of a fresh roll of tape mounted on the successive mandrel adheres to the web of tape being drawn from the depleted roll, thereby causing a web of tape to be drawn from the fresh roll. Thereafter, the control unit controls the cutting unit to cut the web of tape being drawn from the depleted roll, when the second sensor detects rotation of the mandrel in the operation position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on, and claims priority from, Canadian PatentApplication No. 2,227,668, filed Jan. 21, 1998.

MICROFICHE APPENDIX

Not applicable

SUMMARY OF THE INVENTION

This invention relates to a tape splicing device, and in particular to adevice for automatically splicing adhesive tape used in a carton sealingmachine.

Conventional machines currently used to seal cartons, such as, forexample, corrugated cardboard cartons, typically include a work table orframe, the top of which is defined by rollers for slidably receivingcartons. A pair of opposed drive belts frictionally engage the sides ofeach carton, and feed the carton along the length of the machine betweenupper and/or lower tape dispensing heads, which respectively apply tapeto the top and/or bottom and ends of the cartons. The tape is dispensedfrom rolls mounted on arms extending upwardly and/or downwardly from thedispensing heads. When the tape in a roll runs out, it is necessary tostop the machine and replace the used roll with a new roll of tape.

It is preferable to avoid stopping the machine. A proposed solution tothe problem is the use of a stack of interconnected rolls of tape.However, this solution necessitates a complicated structure forinterconnecting the rolls and merely reduces the frequency of machinestoppage. In co-owned U.S. Pat. No. 5,676,792, the teaching of which ishereby incorporated by reference, the present inventor teaches a tapesplicing device which is capable of providing a continuous web of tapeto a carton sealing machine. The device of U.S. Pat. No. 5,676,792comprises a pair of tape spindles mounted on a pivoting arm forreceiving respective rolls of tape. In operation, tape is drawn from oneof the rolls and is fed to a tape dispensing head. When the roll isnearly exhausted, an operator causes the pivoting arm to rotate throughapproximately 180 degrees. Rotation of the arm brings a fresh roll oftape on the other spindle into contact with the web of tape. A tabformed on the fresh roll of tape adheres to the web, thereby causing aweb of tape to be drawn from the fresh roll. At this point the web oftape from the exhausted roll can be cut, such as, for example, by aknife, and the web of tape continues to be drawn from the fresh roll.The operator can then replace the exhausted roll of tape with a freshroll of tape without interfering with the web of tape being drawn fromthe fresh roll. By way of this operation, a continuous web of tape canbe supplied to a tape head in a carton sealing machine, therebyfacilitating continuous, uninterrupted operation of the carton-sealingoperation.

A disadvantage of the above-described device is that its operation isdependent on intervention by an operator, thereby rendering the deviceundesirably labor-intensive and prone to human error.

Thus an object of the present invention is to provide a fully automatictape splicing device capable of operation for extended periods of timewith minimal intervention from an operator.

Accordingly, the present invention provides a multi-roll automatic tapesplicing device in which a platen is rotatably mounted on a supportframe via a shaft. At least two tape mandrels are rotatably disposed onthe platen at a substantially equal distance from the shaft, andsubstantially equally spaced from each other, each mandrel being capableof receiving a respective roll of tape. An index drive is operativelycoupled to the platen, for selectively rotating the platen so as tosuccessively move each mandrel into a predetermined operating positionat which a web of tape can be drawn from a respective roll of tapedisposed on the mandrel, and for moving a mandrel out of the operatingposition when the respective roll of tape is depleted. A first sensor isoperatively mounted on the support frame and capable of detecting adepleted condition of a roll of tape mounted on a respective mandrel inthe operating position. A second sensor is operatively mounted on thesupport frame and capable of detecting rotation of a mandrel in theoperating position. A cutting unit is disposed on the frame and capableof severing a web of tape being drawn from a depleted roll of tape. Acontrol unit is responsive to the first and second sensors such thatwhen the first sensor detects a depleted condition of a roll of tape thecontrol unit controls the index drive to rotate the platen and therebymove the next successive mandrel into the operation position. A tabformed on the end of a fresh roll of tape mounted on the successivemandrel adheres to the web of tape being drawn from the depleted roll,thereby causing a web of tape to be drawn from the fresh roll.Thereafter, the control unit controls the cutting unit to cut the web oftape being drawn from the depleted roll, when the second sensor detectsrotation of the mandrel in the operation position.

The platen can be provided with as few as two mandrels, although threeor more mandrels are preferred because the use of more mandrelsincreases the number of tape splicing cycles which may be completedbefore an operator must install fresh rolls of tape.

The platen can be mounted for rotation either horizontally, orvertically (or at an angle). Furthermore, the frame can be constructedas a free-standing unit, or can be designed to be mounted onto aconventional carton sealing machine.

In an embodiment of the invention, the apparatus comprises a singlesplicing unit composed of an index drive, platen and cutter unit.Alternatively, two or more splicing units can be assembled onto a singleframe, so that a plurality of tape heads can be supplied from a singletape splicing device. In this case, each splicing unit may have its owncontrol unit, or, all splicing units may be controlled by a singlecontrol unit.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention will becomeapparent from the following detailed description, taken in combinationwith the appended drawings, in which:

FIG. 1 is a schematic, isometric view of a conventional carton sealingmachine of the general type with which the device of the presentinvention can be used;

FIG. 2 shows a top view of an automatic tape splicing machine inaccordance with an embodiment of the present invention;

FIG. 3 shows a side view of the automatic tape splicing machine of FIG.2;

FIGS. 4a-4 b schematically illustrate steps in the operation of theautomatic tape splicing machine of FIGS. 2 and 3; and

FIGS. 5a and 5 b respectively show a partially sectioned side view andan end view illustrating a cutting unit usable in the automatic tapesplicing machine of FIGS. 2 and 3.

DETAILED DESCRIPTION

In the following, the present invention is described and illustrated byway of a floor-mounted embodiment having three mandrels mounted on ahorizontally rotating platen. While this illustrated embodiment is fullyoperative, it will be understood that the present invention is in no waylimited to such embodiment. For example, the skilled artisan willrecognize that the device of the present invention can be designed to bemounted on any suitable supporting structure, which may include a frameof a carton sealing machine. Similarly, the platen can be arranged torotate in either a horizontal or an angled plane. Furthermore, whilethree mandrels are used in the illustrated embodiment, the presentinvention can be operated with as few as two mandrels, or as many asfour or more mandrels. Thus it will be seen that the embodimentdescribed in detail herein is illustrative, rather than being limitativeof the present invention.

With reference to FIG. 1, the automatic tape splicing device of thepresent invention is intended for use in conjunction with a machinedesigned to seal cartons, such as, for example, corrugated cardboardcartons (not shown) of the type commonly used for storing and shippingvarious materials and articles. The machine 1 includes a main frame 2defined by side members 3 and end members 4 supported at the corners bylegs 5. The frame 2 includes a plurality of rollers 6 defining a guidesurface 7 for slidably supporting cartons during taping thereof byidentical upper and lower tape heads 8 and 9. The upper tape head 8 ismounted on a crossbar 10 extending between support posts 11 which aresecurely connected to and supported by the side members 3 of the frame2. The lower tape head 9 is mounted in an opening in the guide surface 7defined by the rollers 6. Motor-driven endless belt assemblies 12 orsimilar driving systems are disposed proximal the sides of the guidesurface 7, on either side of the path of travel of the cartons fordriving the latter between the tape heads 8 and 9.

Typically, each of the tape heads 8, 9 carries a respective roll of tape13 (only one is shown in FIG. 1 ) supported by a respective arm 14 whichextends from each tape head 8 and 9. When a roll of tape 13 is depleted,the machine 1, and thus the entire carton sealing operation, must bestopped while the depleted roll is replaced. When an automated tapesplicing machine in accordance with the present invention is used, thearm 14 carrying the roll of tape 13 is replaced by one or more rollers(not shown) which act to guide a web of tape from the automated tapesplicing machine and into the tape head 8, 9 at and angle andorientation similar to that which is obtained when the tape is drawnfrom a roll 13 conventionally mounted on the tape head as illustrated inFIG. 1. By this means, the carton sealing machine 1 can be suitablyadapted to receive tape continuously delivered to the tape heads withminimal modification of the tape-heads themselves. This allows theautomated tape splicing machine of the present invention to be readilyincorporated into existing production lines while minimizing the cost ofmodifying existing carton sealing equipment.

In the following description, a single automatic tape splicing machineis described for supplying tape to the lower tape head 9 of a cartonsealing machine 1. However, it will be understood that a similararrangement will advantageously be provided for supplying tape to theupper tape head, the only significant difference being the provision ofsuitable rollers for guiding the web of tape to the respective tapeheads. It is considered that the introduction of such additional rollerswill be well within the purview of one skilled in the art.

Referring now to FIGS. 2, 3, and FIGS. 4a-4 d, the automatic tapesplicing machine 15 of the present invention generally comprises aplaten 16 rotatably mounted on a support frame 17 via a shaft 18. Tapemandrels 19 are rotatably disposed on the platen 16 at a substantiallyequal distance from the shaft 18, and substantially equally spaced fromeach other. Each mandrel 19 is designed to securely retain a respectiveroll 20 of tape, and to rotate as a web of tape 21 is pulled from acorresponding roll 20. In the illustrated embodiment, the platen 16 isconfigured generally as an equilateral triangle with the shaft 18located at its centroid. The three mandrels 19 a-19 c are mountedproximal respective vertices of the triangular platen 16. In anembodiment having four mandrels 19, the platen 16 would conveniently besquare or X-shaped, with mandrels 19 being mounted at respectivecorners. The platen 16 serves to provide a rotatable mounting platformfor supporting the mandrels 19 (and respective rolls of tape 20) and canbe fabricated of any convenient material providing suitable strength,rigidity and resilience, such as, for example, steel or aluminum plate.

An index drive 22 is operatively coupled to the platen 16, eitherdirectly or via the shaft 18, for selectively rotating the platen 16 inthe manner described in further detail below. The index drive 22 can bepowered by convenient means, such as, for example, using an electricmotor coupled to the shaft by way of a suitable gear, belt, chain orsimilar power transmission unit. Alternatively, a pneumatically orhydraulically powered drive unit can be provided. The index drive 22 iscontrolled by a suitable control unit 23 to hold the platen 16 in afixed condition so that a mandrel 19 a is maintained at a predetermined“active position” (at the top, in each of FIGS. 4a-4 d) while a web oftape 21 a is pulled from a respective roll 20 a mounted on that mandrel19 a. When the supply of tape on the roll 20 a is depleted, the indexdrive 22 rapidly rotates the platen 16 to bring the next mandrel 19 bcarrying a fresh roll of tape 20 b into the active position so that aweb of tape 21 b can be pulled therefrom. This operation will bedescribed in greater detail below.

A depleted roll sensor 24, is operatively mounted on a suitable bracket25 secured to the support frame 17 proximal the active position. Thedepleted roll sensor 24 is arranged to detect a depleted condition of aroll of tape 20 from which a web 21 of tape is being drawn. The depletedroll sensor 24 can conveniently be provided as anopto-emitter/photo-detector combination arranged, for example, to detecta depleted condition of the roll of tape by reflecting light off theroll in question. In this situation, while the photo-detector detects areflected light, it is determined that the roll of tape has not yetreached a depleted condition. Conversely, when a reflected light is notdetected, it is determined that the roll of tape has reached a depletedcondition. In an alternative arrangement, the photo-detector andopto-emitter can be arranged on opposite sides of the roll of tape, sothat a full roll of tape will interrupt the light path between theemitter and the photo-detector In this case, if the photo-detectordetects light from the emitter, it is determined that the roll of tapehas reached a depleted condition.

As a further alternative, the depleted roll sensor 24 could be providedas an idler wheel mounted on a spring-loaded arm and running on the rollof tape in the active position. Thus the angle of the spring-loaded armis indicative of the amount of tape remaining on the roll, and adepleted condition of the roll of tape can be indicated by amicro-switch suitably positioned to be activated by the spring-loadedarm.

In any of the above arrangements, the depleted roll sensor 24 generatesa signal indicative of whether or not the roll of tape has reached adepleted condition, and transmits this signal to the control unit 23 bya suitable conductor (not shown).

A rotation sensor 26 is also operatively mounted on the support bracket25 and arranged to detect rotation of a mandrel 19 in the activeposition. The rotation sensor 26 can be conveniently provided as aconventional emitter/detector unit arranged to detect light reflectedfrom suitable reflective indices (not shown) formed on the mandrel 19,or to detect light passing through holes or slots (not shown) suitablyformed in the mandrel 19. Alternatively, the rotation sensor 26 can beprovided as a conventional Hall-effect sensor. With any of the abovearrangements, the rotation sensor 26 generates a signal indicative ofrotation of the mandrel 19 in the active position, and transmits thissignal to the control unit 23 by a suitable conductor.

A cutting unit 27 is disposed on the frame 17 for severing a web of tape21 a being drawn from a depleted roll of tape 20 b (see FIGS. 4a-4 d).In the embodiment illustrated in FIG. 5, the cutting unit 27 generallycomprises a housing 28 secured to the frame 17, a slider plate 29slidably disposed on tracks 30 of the housing 28, a knife assembly 31mounted on a forward end of the slider plate 29, and an actuator unit 32for driving the slider plate 29 and knife assembly 31 between aretracted position (shown in dotted lines in FIG. 5) and a cuttingposition (shown in solid lines in FIG. 5). The knife assembly 31includes a knife blade 33 securely retained on the slider plate 29 by aknife carrier 34. The housing 28, slider plate 29 and knife carrier 34can conveniently be constructed of any conveniently suitable material,such as, for example, steel, aluminum, or suitable plastic. The knifeblade 33, which will conveniently be formed of high-strength steel toprovide a long-lasting edge, is secured to the knife carrier 34 by anysuitable means, such as, for example, by means of nuts, bolts or screws.

The actuator unit 32 can conveniently be provided as a conventionallinear actuator driven by hydraulic or pneumatic power, or alternativelycould be provided as an electromagnetically activated solenoid.

As shown in FIGS. 2, 3 and 4, the cutting unit 27 is arranged behind theoperating position of the platen 16 as seen from the direction ofrotation of the platen 16, and knife blade 33 is held, in the retractedposition. outside the path of a mandrel 19 as the platten 16 is rotated.With this arrangement, when the platen 16 rotates to bring a fresh rollof tape 20 b into the active position, the mandrel 19 a carrying thedepleted roll 20 a is moved past the cutting unit 27. Following rotationof the platen 16, the web of tape 21 a streaming from the depleted roll20 a lays across the path of motion of the knife assembly 31, so thatthe knife blade 33 will sever the web of tape 21 a when the actuatorunit 32 is activated to slide the knife assembly 31 from the retractedposition to the cutting position. Following the severing of the tape 21a from the depleted roll 20 a, the knife actuator 32 returns the knifeassembly 31 to the retracted position in preparation for the nextrotation cycle of the platen 16.

The control unit 23 is operatively mounted on the support frame 17 forcontrolling rotation of the platen 16 and activation of the cutting unit27. The control unit 23 is conveniently provided as a microprocessorcircuit operating under suitable program control, and includes inputjacks for receiving signals from each of the depleted roll and rotationsensors 24 and 26. Alternatively, the control unit could comprise arelay circuit responsive to the signals from the depleted roll androtation sensors 24 and 26. In general, the control unit 23 isresponsive to the signals generated by the depleted roll and rotationsensors 24 and 26 to provide the following operation sequence, asillustrated in FIGS. 4a-d.

When the depleted roll sensor 24 detects a depleted condition of a rollof tape 20 a, the control unit 23 controls the index drive 22 to rotatethe platen 16 through one sector (defined as the angular separationbetween adjacent mandrels 19) in the direction indicated by the arrow inFIG. 4b. This rotation moves the next successive mandrel 19 b and thus afresh roll of tape 20 b into the active position, and simultaneouslymoves the mandrel 19 a carrying the depleted roll 20 a out of the activeposition and past the cutting unit 27, while continuing to draw a web oftape 21 a from the depleted roll 20 a. The fresh roll of tape 20 b beingmoved into the active position contacts the adhesive face of the web oftape 21 a being drawn from the depleted roll 20 a, which causes thefresh roll of tape 20 b (and its mandrel 19 b) to begin rotation. Apreviously formed tab on the free end of the fresh roll of tape 20 b isthus brought into contact with the adhesive face of the web of tape 21 afrom the depleted roll, whereupon a web of tape 21 b (bonded to the web21 a from the depleted roll) begins being drawn from the fresh roll 20b.

Upon detection of continued rotation of the mandrel 19 b carrying thefresh roll of tape 20 b, the control unit 23 activates the knifeactuator 32 of the cutter unit 27 to quickly and forcefully drive theknife assembly 31 to the cutting position, thereby severing the web oftape 21 a being drawn from the depleted roll 20 a (FIG. 4d). The web oftape 21 b continues being drawn from the fresh roll 20 b after severingof the web from the depleted roll, thereby providing a continuous supplyof the tape to the carton sealing machine 1. Following cutting of theweb of tape 21 a from the depleted roll 20 a, the actuator 32 of thecutter unit 27 moves the knife assembly 33 to its retracted position soas to be ready for the next cycle.

It will be apparent to those skilled in the art that the presentinvention can varied without departing from the scope of the presentinvention. For example, the specific embodiment described in detailabove comprised a platen having three mandrels. Those skilled in the artwill recognize, however, that the present invention can be implementedwith two or more mandrels. Similarly, the knife assembly 31 describedabove is of a “linearly actuated” type. It will be seen however, that apivoting knife assembly would work as well. Indeed, virtually any meansfor reliably severing the web of tape from the depleted roll can be usedwith the present invention, the only restriction being that the tapecutting mechanism must not interfere with rotation of the platen duringa tape splicing cycle. Thus it will be seen that the above-describedembodiment is illustrative, rather than being limitative of the presentinvention.

What is claimed is:
 1. A multi-roll automatic tape splicing devicecomprising: (a) a support frame; (b) a platen rotatably mounted on saidsupport frame; (c) a shaft rotatably supporting said platen and saidframe; (d) at least two tape mandrels rotatable on said platen, saidmandrels being spaced equidistant from said shaft, and spaced apart fromeach other, each mandrel being adapted to receive a roll of tape; (e) anindex drive for selectively rotating the platen to successively move amandrel carrying a fresh roll of tape into a predetermined operatingposition in which a web of tape can be drawn from the fresh roll of tapeand for moving a mandrel carrying a nearly depleted roll of tape fromwhich a web of tape is being withdrawn out of the operating positionwhen the roll of tape is nearly depleted; (f) a first sensor on thesupport frame for detecting a nearly depleted condition of a roll oftape in the operating position; (g) a second sensor on the support framefor directly detecting rotation of a mandrel in the operating positionat the moment when the roll of tape is drawn from the fresh roll oftape; (h) a cutting unit on the frame for severing a web of tape beingdrawn from a nearly depleted roll of tape; and (i) a control unitresponsive to the first and second sensors for actuating the index driveto rotate the platen, when said first sensor detects a nearly depletedcondition of the nearly depleted roll of tape, thereby moving a mandrelcarrying a fresh roll of tape into the operating position, whereby a tabon the end of the fresh roll of tape adheres to the web of tape beingdrawn from the nearly depleted roll causing a web of tape to be drawnfrom the fresh roll, and when the second sensor detects rotation of themandrel carrying the fresh roll of tape in the operating position, thecontrol unit immediately actuates the cutting unit to cut the web oftape being drawn from the nearly depleted roll.
 2. A multi-rollautomatic tape splicing device as claimed in claim 1 including three ormore mandrels.
 3. A multi-roll automatic tape splicing device as claimedin claim 1, wherein the platen is mounted for rotation in asubstantially horizontal plane.
 4. A multi-roll automatic tape splicingdevice as claimed in claim 1, wherein the platen is mounted for rotationin a substantially vertical plane.
 5. A multi-roll automatic tapesplicing device as claimed in claim 1, wherein the platen is mounted forrotation in a plane which is inclined with respect to horizontal.
 6. Amulti-roll automatic tape splicing device as claimed in claim 1, whereinthe frame is a free-standing unit.
 7. A multi-roll automatic tapesplicing device as claimed in claim 1, wherein the frame is designed formounting on a conventional carton sealing machine.
 8. A multi-rollautomatic tape splicing device as claimed in claim 1, wherein the indexdrive, platen and cutting unit define a splicing assembly.
 9. Amulti-roll automatic tape splicing device as claimed in claim 8,comprising a single splicing assembly for supplying a web of tape to asingle tape head of a carton sealing machine.
 10. A multi-roll automatictape splicing device as claimed in claim 8, comprising two or moresplicing assemblies for simultaneously supplying webs of tape to tapeheads of one or more carton sealing machine.
 11. A multi-roll automatictape splicing device as claimed in claim 10, comprising a control unitfor controlling each splicing assembly.
 12. A multi-roll automatic tapesplicing device as claimed in claim 10, comprising a single control unitfor controlling all of the splicing assemblies.